Sleep disordered breathing is common throughout the population, and some sleep disorders may be attributable to disorders of the respiratory tract. Sleep apnea may be a disorder where a person temporarily stops breathing during sleep. A hypopnea may be a period of time where a person's breathing becomes abnormally slow or shallow. In some cases, a hypopnea precedes an apnea event. Snoring may be caused by mucus build up in the upper respiratory tract, and/or excessive tissue causing cyclic full or partial blockages of the nose. Other breathing difficulties, not necessarily related to sleep but which breathing difficulties become more pronounced during sleep, may be caused by full or partial blockages of the nares, such as by a tumor or polyp.
Sleep disordered breathing and other breathing difficulties may be diagnosed in a sleep lab, or possibly by a device which the patient takes home and wears throughout the day or during sleep. For a proper diagnosis, particularly in the case of a tumor or polyp, the various ports of a test device need to be coupled to the naris for which they were intended; however, currently available nasal cannulas have device-ends (as opposed to patient-ends) that are identical and easily switched when being coupled to a test device.